This invention relates to a novel silicon-containing copolymer useful for forming a heat resistant coating and to a method of producing same
As heat resistant polymers, there have been proposed fluorine-containing polymers, polyimides, aromatic polyamides, polyimide bendazols, etc. These polymers, however, cannot show a heat resistance at a temperature of more than 300.degree. C. There are also known highly heat resistant, metal-containing polymers such as metal-containing silicone resins and polymetallosiloxane. These polymers can withstand a high temperature of about 500.degree. C. Because of the large, three-dimensional network structure thereof, however, the metal-containing polymers lack flexibility, so that the use thereof is limited to only specific applications.
JP-A-2-175726 discloses a silazane block copolymer containing inorganic polysilazane sections and organic polysilazane sections. While the silazane copolymer shows both high heat resistance and improved flexibility, the mechanical strengths such as elongation and tensile strength are not satisfactory.